|Birth of the solar system (National Geographic)|
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The Solar System's birth was far from peaceful. Witness the spectacular explosion known as the "Big Bang" from a documentary by National Geographic.
As our nebula began to collapse under its own gravity and spin faster, a dense clump of matter formed in the centre. It’s called a protostar. At first, its heat was due to friction. But when the clump reached 18 million degrees Fahrenheit, nuclear fusion kicked in.
Four-and-a-half billion years ago, our star was born. Hydrogen atoms fused together to form helium, and in the process, released photons. It’s the first light made by our sun. And it will keep on shining for four billion years. A vast nuclear furnace nearly a million miles across. From a distance, this process seems almost peaceful, with the sun’s power gently radiating out into the early solar system.
There was all sorts of activity going on, things were changing rapidly, violence, explosions, intense radiation. We had a pretty spectacular origin, I think.
Recent research suggests the solar system’s birth was far from peaceful. Our sun may, in fact, have been born out of one of the most violent events in the cosmos: the explosive death of another star.
And even before that, it seems there was an explosion so huge, that it created an entire universe: the Big Bang. No one knows what caused it, but we think that the bang created space, time, and all the matter in the universe.
Yet for astrophysicists such as Professor Stan Woosley, there’s a puzzle. The Big Bang produced almost none of the 88 naturally occurring chemical elements.
When we look around, we don’t just see hydrogen and helium. We see planets and people, and we’re made out of carbon and oxygen and planets are made out of iron and silicon. And that didn’t all come from the Big Bang, it had to come from somewhere else.
Here on earth, we have learned how to create new elements for ourselves. Nuclear technology. The same thing happens inside stars. Hydrogen and helium from the Big Bang fuse to form heavier elements, and if the star is big enough, at the end of its life, it does something spectacular: It explodes.
The energy of a supernova explosion is essentially equal to all of the energy that the sun will put out in its 10-billion-year lifetime.
NEBULA= A diffuse mass of interstellar dust or gas or both, visible as luminous patches or areas of darkness depending on the way the mass absorbs or reflects incident radiation. The plural form is “nebulae” or “nebulas”.
SPIN= To rotate quickly. Irregular verb: spin – spun/span – spun/span
CLUMP= A thick grouping of things or mass.
ITS HEAT WAS DUE TO FRICTION= Its heat was originated by friction, caused by friction.
NUCLEAR FUSION KICKED IN= Nuclear fusion took place (happened).
PHOTONS= Particles of light.
VAST= Huge, very very big.
FURNACE= An intensely hot place (for example the place created to melt metals).
THE SUN’S POWER= We use the Saxon genitive with people and time expressions, but sometimes we use it with some other things too.
GOING ON= Happening.
FAR FROM PEACEFUL= Not peaceful at all (completely violent).
MATTER= A physical body or substance.
YET, FOR ASTROPHYSICISTS…= Nevertheless, for astrophysicists…
A PUZZLE= A mystery, something we don’t understand.
CHEMICAL= This is one of the words where CH is pronounced like K (other examples are: school, architect, technology, etc.)
IRON= In British English the R here is not pronounced (but this is American English and they pronounce it).
SOMEWHERE ELSE= Some other place.
A SUPERNOVA= An event caused by the explosion of a star.